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    Re: Spherical triangle split by right triangles
    From: Robert VanderPol II
    Date: 2016 Jan 23, 20:21 -0800

    Bob Goethe wrote:

    No, that is the magic of spherical geometry.  A line takes off from a point at a 90° angle to a meridian, and it does not remain parallel to a latitude line.  (Probably, that means it was never PRECISELY parallel to a latitude line, but it appears so for short distances; this is analogous to how it is that rhumb lines are the same as great circle lines for short distances.)

    Right, forgot that Latitudes are not great circles.

       
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